As pointed out, the "positronic brain" reference from the February 1981 screenplay was explicitly to the second generation of androids, before Replicants (who were the "synthogenetic" third generation):Hi!
Consistency with the source material is absolutely a priority. The term positronic was used in Hampton Fancher and David People's 1981 screenplay draft of Blade Runner, which is considered canon. That said, if the term causes confusion, we might consider removing it.
So, even taking this as canon (though this was never referenced in the dialogue or stage directions in that script - this was just an opening scroll that was never used in the theatrical release of the film or any of the working/director's cuts of the film), the positronic brain thing is referring to the pre-Nexus 6 models, not to the Nexus 6's as the RPG currently has it.android (an'droid) n, Gk. humanoid automation. more at robot./ 1. early version utilized for work too boring, dangerous or unpleasant for humans. 2. second generation bio-engineered. Electronic relay units and positronic brains. Used in space to explore inhospitable environments. 3. third generation synthogenetic. REPLICANT, constructed of skin/flesh culture. Selected enogenic transfer conversion. Capable of self perpetuating thought. paraphysical abilities. Developed for emigration program.
WEBSTER'S DICTIONARY New International (2012)
The only version of the "dictionary quote" scroll that made it into any version of the film was the one used for the initial Workprint (which was also used in some early sneak preview screenings), which dropped all references to "positronic brains" completely:
The reference to "positronic brains" probably should be changed to make it about the pre-Replicant generations of androids and to make it clear that it does not refer to the Nexus 6 (if not just dropped entirely).REPLICANT\rep'-li-cant\n. See also ROBOT (antique): ANDROID (obsolete): NEXUS (generic): Synthetic human, with paraphysical capabilities, having skin/flesh culture. Also: Rep, skin job (slang): Off-world uses: Combat, high-risk industrial, deepspace probe. On-world use prohibited. Specifications and quantities - information classified. New American Dictionary. Copyright (C) 2016